Crimean-Congo hemorrhagic fever (CCHF) is a widespread tick-borne viral disease that can affect humans. It is a member of the Bunyaviridae family of RNA viruses. Clinical disease is rare in infected mammals, but it is commonly severe in infected humans. Outbreaks of illness are usually attributable to handling infected animals or people.
The causative organism is found in Asia, Eastern Europe, the Middle East, a belt across central Africa and South Africa and Madagascar. The main environmental reservoir and vector for the virus is hard ticks. Ticks carry the virus to domestic animal stock. Sheep, goats and cattle can develop viremia, but tend not to fall ill. Tick species that have been identified as infected with this virus include Argas reflexus, Hyalomma anatolicum, Hyalomma detritum, Hyalomma marginatum and Rhipicephalus sanguineus. 
The onset of CCHF is sudden, with initial signs and symptoms including headache, high fever, back pain, joint pain, stomach pain, and vomiting. Red eyes, a flushed face, a red throat, and petechiae (red spots) on the palate are common Symptoms may also include jaundice, and in severe cases, changes in mood and sensory perception. As the illness progresses, large areas of severe bruising, severe nosebleeds, and uncontrolled bleeding at injection sites can be seen, beginning on about the fourth day of illness and lasting for about two weeks.
Animal herders, livestock workers, and slaughterhouses in endemic areas are at risk of CCHF. Healthcare workers in endemic areas are at risk of infection through unprotected contact with infectious blood and body fluids. Individuals and international travelers with contact to livestock in endemic regions may also be exposed. In documented outbreaks of CCHF, fatality rates in hospitalized patients have ranged from 5% to as high as 80%.
Previous attempts to develop preventative treatment are as follows. In a USSR/Bulgarian CCHF vaccine developed in 1974 comprised an inactivated antigen from CCHF virus strain V42/81. It was generated from suckling mouse brain preparations, and so is unsuitable for FDA approval in the U.S. There is also a recombinantly produced construct comprising G1 (Gc), or G2 (Gn) glycoprotein ectodomains or portions thereof. However, no study exists to suggest any efficacy for this approach. Full effectiveness of this construct may be limited to the specific strain where the selected glycoproteins originated. There is no established virus-specific treatment. Ribavirin is thought to be effective in vitro, and has been used in human subjects during outbreaks. There are conflicting reports as to effectiveness, with the more recent ones showing limited to no effectiveness against CCHF virus in vivo.
The Department of Defense views CCHF virus as a potential threat to the U.S. armed forces when operating in countries endemic to the virus. These geographical locations include but are not limited to Afghanistan, Pakistan, and the Middle East. The need for preventative treatment of was underscored by death of a U.S. soldier from CCHF viral infection in 2009.